Elastic fluid compressor or motor



July 20, 1943. R. BECKMAN ELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan.28, 1939 3 Sheets-Sheet 1 r INVENTOR ATTORNEY July 20, 1943. R. BECKMANELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan. 28, 1939 5 Sheets-Sheet 254 W fiv2-\ xd I v 40 a 4 Q WM,

INVENTOR ATTORNEY July 20,1943. R. BECKIIVIAN 2,324,903

ELASTIC FLUID COMPRESSOR OR MOTOR Filed Jan. 28, 1939 3 Sheets-Sheet 3INVENTOR 6 J3 moi/524M ATTORNEY Patented July 20, 1943 ELASTIC FLUIDLJMPRESSOR OR MOTOR Richard Beckman, New York, N. Y.,'assignor ofone-half to Otto Gries, New York, N. Y.

Application January 28, 1939, Serial No. 253,252 4 Claims. (01. 230-152)This invention relates to rotary devices whereby elastic fluid, such asair, may be compressed and conversely the device may be driven as amotor by means of compressed elastic fluid.

One of the main objects of the invention is to provide a device of thecharacter described which shall have. the losses of power in operation,greatly reduced.

Another of the main objects of the invention is to provide a. device ofthe character described wherein the wear of parts shall be reduced to aminimum.

A further object of the invention is to provide the mounting on therotor of the radially movable vanes.

A further object of the invention is to provide in apparatus of thecharacter described, a rotor having end heads serving as lateral guidesfor the vanes and preventing lateral friction of the rotor against theend heads of the stationary housing.

A further object of the invention is to provide improved means forinsuring the forcing of the rotor vanes outwardly into contact with thesurrounding cylindrical wall.

A further object of the invention is to provide a rotor mounted by stubshafts or trunnions at its ends instead of having a shaft extendingentirely through the rotor as formerly.

A further object of the invention is to provide a freely rotatablecylinder encircling the rotor vanes, and. against which the vanes bear,whereby the friction and wear of the parts is greatly decreased.

A further object of the invention is to provide freely rotatable ringsas bearings for mounting upon the stationary casing, the cylinderencircling the vanes as above referred to.

A further object of the invention is to provide fluid pressure means forforcing the vanes from the centre outwardly whereby undesirable bores orrecesses in the rotor are made unnecessary.

A further object of the invention is to supply oil to the vane bearingsby introducing it into the interior of the rotor hub.

A further object of the invention is to supply fluid pressure to theinterior of the rotor hub, for forcing the vanes outwardly.

Other and ancillary objects of the invention will appear hereinafter.

In the accompanying drawings which illustrate the invention- Fig. 1 is asection on the line |l of Fig. 3;

Fig. 2 is a section on the line 22 of Fig. 1;

Fig. 3 is an end elevation of the device viewed from the left hand ofFig. 1;

Fig. 4 is a fragmentary section on the line 44 of Fig. 2 showing themanner of securing the end head of the rotor;

Fig. 5 is a fragmentary section on the line 55 of Fig. 2 showing themanner of mounting the roller bearing for a vane;

Fig. 6 is a fragmentary section on the line II of Fig. 3 but showing amodified form of floating bearing rings for the floating cylindersurrounding the rotor vanes; and

Fig. 7 is a diagram showing the fluid control when the device isoperated as a motor.

Referring to the drawings, the apparatus is a compressor (or converselya motor) of the rotary type wherein a rotor eccentrically mounted withina casing has vanes carried by the rotor which are forced outwardlyagainst the surrounding walls.

As shown in the drawings, and referring first to Figs. 1 to 5 inclusive,the casing of the apparatus comprises a casing including the cylindricalportion 8 to which are secured the end heads 2 and 3. Within the casingis mounted a freely rotating cylinder 4, the ends of which fit intorecesses in the end heads 2 and 3, and this cylinder d is supported atone end from the body of the casing by means'of a series 5 of overlyingrings or bands, and the other end of the rotor is supported from thecasing by means of a series of overlying rings or bands 5'. Both sets ofbands extend entirely about the cylinder 5 and support natedconstruction, and in the instance illustrated bands 6 and i, each withan offset flange I 8, are provided on each side of the band 5, acting toprevent the latter from coming into wearing contact either with the endhead 9 of the casing, or with the shoulder in upon the cylindrical partof the casing; and an additional band H is shown;-the entire assemblyconstituting a very easy-running bearing structure. The clearance l2 maybe oil-filled to aid lubrication and to carry ofi the heat of operation.

Thus, wall friction is greatly reduced and higher speeds can be attainedthan with existing rotary vane compressors. Since the auxiliary cylinder4 is to be regarded as a rotor, and is floating, preferably, th vanes Vextending from the rotor proper, which is designated generally by thereference character R, will rotate the auxiliary rotor 4, by theirpressure exerted against the saute, at approximately the same speed, andthus again diminish friction between the vanes, allowing great speed anddisplacements per time unit.

From the foregoing it will be understood that it is not necessary toprovide for positive driving of the auxiliary rotor, but it is notintended to exclude the possibility of such actuation where founddesirable and suitable.

In pursuance of a general object of the inventionto reduce friotionthevaned rotor R is provided with certain novel features, as follows:

(1) It is provided with end heads l3 and I4, which rotate with it andserve as lateral guides for the vanes V preventing lateral friction ofthe rotor against the stationary end heads l5 and I6 of the casing,between which and the rotor head there may desirably be a slightclearance as indicated at H; these rotor heads are preferably formed asradial flanges upon hollow stub shafts or trunnions l8 and I9 which takethe place of the usual shaft running through the vaned rotor; and inthis novel structure a ball-bearing, as 20, is provided, for eachtrunnion, and fitted in suitable bosses 2i, 22 carried by the casing endheads l5 and I6; 2. known form of stufling box G is shown at one end ofthe rotor'and a packing ring 23 at the other end.

The hub 24 is provided with an axial bore 25 to which lubricant may beintroduced through a, nozzle 26 screwed at 21 into the boss 2| and aconduit 28 is provided to place the cavity 29 of the boss incommunication with the high-pressure side of the device so that a plenumof pressure may be maintained in the bore 25, tending to drive lubricantthrough ducts 30 which pierce the hub for that purpose communicatingindividually with the inner ends of the vane slots as shown at 3| inFig. 2. Thus lubricant can be fed to the vanes V under pressure and atthe same time, in pursuance of another object of the invention, thevanes are biased to their outer working position.

(2) Each vane has a head 33 which fits snugly in its slot 33 and theshanks 34 are reduced in diameter as at 35 to diminish friction; for thesame purpose the wall of each vane slot is enlarged as at 36 to affordclearance, and at this region each of the spokes 31 of the rotor has anenlargement 38 in which is formed a recess 3'9 that serves as a bearingfor an anti-friction member 40 shown as a hollow roller in the instancesillustrated but which may be of any suitable form.

(3) The vane slots 33 are not disposed in true radial alignment with theaxis of rotation, but each is formed at an angle to the radius whichintersects the centre line of the slot at the mouth thereof, so thateach vane is inclined, as illustrated clearly in Fig. 2, preferably withits outer end 34 ahead of the head 32. By this arrangement the inventionprevents edging of the vanes at the in-stroke, since a certain thrust isexerted upon each vane, backwards of the theoretical centre line of thevane, as well as backwards of the direction of rotation of the rotor. Itwill be observed also that the rollers 40 aid to take up the sidewisecomponent of the thrust. The rotor may be secured to its end heads, asby screws 4|, tapped into flanges 42 (see Fig. 4).

Suitable provision may be madefor cooling the structure as byconventional ribs 43, also by water jackets (not shown) whereverdesired.

In Fig. 3 the inlet is shown at 44 and the outlet at 45, thes positionsbeing optional, of course, and variable to suit the exigencies ofparticular installations, as are other structural features of thecasing.

From the foregoing disclosure, it will be understood readily thatsubstantial advantages are obtained in addition to those already noted,and among which may be mentioned the following:

(a) Volumetric efiiciency is very much higher than with any othercompressor, due to the complete displacement and the absence of wastespace.

(1)) pressures at all speeds are uniform.

(c) vibrationless and noiseless operation is secured.

(d) not only is friction greatly reduced, but abrasive action isvirtually eliminated, owing to the exclusion of dust, which inconventional vanetype compressors, piles up ahead of the vanes at theircontacting ends.

(e) the rotor end-covers form a lateral seal being recessed into thehousing covers.

(I) wear and tear of the vanes is compensated automatically and aperfect seal maintained at all times.

When the device is'operated as a motor the source of fluid pressurewould be connected to the outlet 45 but the vanes V must be in extendedposition when the power is applied. Accordingly a control device shouldbe employed whereby the pressure would be first applied to the innerends of the vanes, forcing them into extended position in the manner asdescribed above and the pressure then applied to the opening 45 (outletwhen operating as compressor). Such a control is schematically shown inFig. 7. In that figure the pipe 50 connects the cylinder 5| with thechamber at the inner ends of the vanes V, while a pipe 52 connects thecylinder with the opening 45. Also a pipe 53 from a source of motivefluid pressure, connects with the cylinder 5|. When the piston 54 whichslides in the cylinder, and may be moved by the hand piston rod 55, isin the position as shown in the draw-' ings, the fluid pressure of pipe53 is cut off from both pipes '50 and 52. As the piston is slid to theright (Fig. 7) however, the end of the pipe 50 is first uncoveredwhereupon the vanes are forced into extended (outward radially) positionand then as the piston is moved further to the right the pipe 52 isuncovered and motive pressure is supplied to the motor. Obviously thepower may be shut 01f by returning the piston to its original position.

While the invention has been illustrated in what is considered its bestapplication, it may have other embodiments without departing from itsspirit and is not, therefore, limited to' the structures shown in thedrawings.

What I claim is:

1. A fluid-pressure device comprising in combination a main cylindercasing, an eccentric rotor piston with reciprocating vanes rotatablymounted in said casing, fluid-pressure chambers between said vanes andan auxiliary cylindrical rotor concentrically mounted in said casing andsurrounding said vanes and the fluid-pressure chambers therebetween anda series of bearing rings at each end of said rotor through which saidcylindrical rotor is mounted upon said casing, said cylindrical rotorbeing freely rotatable, the bearing rings of each series being arrangedone outside the other, the outer ring of the said series bearing againstthe said casing and the inner ring of said series bearing against saidcylindrical rotor, said bearing rings each having a cross sectiongreater axially than radially of said rotor and said rings bearingupon'one another, said casing or said rotor for the greater portion oftheir extent axially of said rotor,'said rings being slidable upon, andfreely rotatable with relation to each other and to said cylindricalrotor and to said casing and to said vanes, and intakeand dischargemeans for said chambers.

2. A fluid-pressure device having the features claimed in claim '1 inwhich at least one of the said bearing rings has a radial flangeinterposed between another of the rings and a wall of said casing.

3. A fluidpressure device comprising in combination a stationary maincylinder casing, an eccentric rotor piston with reciprocating vanes,rotatably mounted in said casing, said eccentric rotor piston having ahub and radial slots for said vanes, each of said vanes having an innerhead having-a snug slide fit in its vane slot and a shank of lessthickness, the opening of said slot being of a larger cross sectionalarea than the vane for a substantial distance inward from the mouth ofthe slot, said slots having a recessed wall portion, an anti-frictionmember for each vane mounted rotatably in said recessed portion 4. Afluid-pressure device comprising in comprising in combination astationary main cylinder casing, an eccentric rotor piston withreciprocating vanes, rotatably mounted in said casing, said eccentricrotor piston having a hub and radial slots for said vanes, each of saidvanes having an inner head having a snug slide fit in its vane slot anda shank of less thickness, the opening of said slot being of a largercross sectional area than the vane tor a substantial distance inwardfrom the mouth of the slot, said slots having a recessed wall portion,an anti-friction roller for each vane mounted rotatably in said recessedportion of the slot wall, said roller being disposed in the slot wallwhich drives the vane, means for forcing the vanes outwardly by elasticfluid-pressure and fluid inlet and outlet ports RICHARD BECKMAN.

